Amate Medical's 3D-Printed Fully Bioresorbable Vascular Stents: Disrupting the Multi-Billion-Dollar Market

Cardiovascular diseases have become the leading threat to human health. According to the "Report on Cardiovascular Diseases in China 2018," 290 million people in China suffer from cardiovascular diseases, including 11 million patients with coronary heart disease. Data shows that the mortality rate of cardiovascular diseases ranks first among all causes of death, higher than that of cancer and other diseases.

For patients with coronary heart disease (CHD), percutaneous coronary intervention (PCI) with stent implantation has become the gold standard of treatment. On April 27, 2019, at the 22nd National Interventional Cardiology Forum, Professor Huo Yong released data on interventional therapy for CHD: In 2018, the total number of PCI procedures performed in China was 915,256, with an average of 1.46 stents implanted per patient. The estimated total number of stents used throughout the year was approximately 1.33 million. Compared with 2017, the number of CHD interventional therapy cases in 2018 increased by 21.5%.

The data were primarily sourced from the online direct reporting system (705,970 cases), additional cases verified by provincial quality control centers (159,522 cases), and data from the military hospital quality control system (49,764 cases).

The Development of Cardiac Stents Has Created a Market Worth Over RMB 20 Billion, with Domestically Produced Stents Accounting for 80% of the Chinese Market.

Although coronary stenting has become the gold standard for treating patients with coronary artery disease, patients are required to take anticoagulant medications for life post-procedure to prevent in-stent thrombosis. Even after physical recovery, many patients remain troubled by the presence of a metallic stent in their body, which they perceive as affecting their normal daily life and work.

To this end, scientists have developed a bioresorbable scaffold that can dissolve autonomously within the body and be absorbed by the host tissue. When implanted at the site of vascular stenosis, this scaffold provides structural support to the vessel. Once the vessel has healed, the scaffold becomes covered by neointima, gradually degrades, and is ultimately absorbed by the body, leaving no residual material. This approach avoids the various adverse effects associated with the long-term presence of permanent metallic implants, such as potential chronic local inflammatory responses and the risk of thrombosis.

Abbott Laboratories’ Absorb, a bioresorbable vascular scaffold for the treatment of coronary artery disease, was the first fully bioresorbable coronary stent to be used clinically in the United States, but it has since been discontinued. Lepu Medical’s Neovas, a fully bioresorbable coronary stent, received product registration approval from China’s National Medical Products Administration (NMPA) in February 2019, becoming the first fully bioresorbable coronary stent successfully launched on the Chinese market. Additionally, Shandong Huian’s Xinsorb stent is currently undergoing product registration. Other domestic companies, including MicroPort (Shanghai), Biostar, and Maiquan, are conducting clinical trials for their respective products.

Beijing Advanced Medical Technologies Co., Ltd. (hereinafter referred to as "AMT") is also a high-tech company dedicated to the development of fully bioresorbable vascular stents. Its fully bioresorbable coronary drug-eluting stent system, AMSorb™, is currently undergoing clinical trials. Professor Huo Yong from Peking University First Hospital serves as the Principal Investigator, while Dr. Zhou Yujie, Deputy President of Beijing Anzhen Hospital, serves as the Co-Principal Investigator.

The clinical trial of the AMSorb™ stent was approved by the National Medical Products Administration on April 1, 2019, and received approval from the Ethics Committee of Peking University First Hospital on July 3.

On July 23, Professor Chen Ming from Peking University First Hospital successfully completed the first implantation of the AMSorb™ stent. To date, nearly 10 clinical implantations of the AMSorb™ stent have been performed at this hospital. Another product from AMT Medical Inc., the fully bioresorbable peripheral vascular stent PeriSorb, is currently applying for entry into clinical trials.

To gain a deeper understanding of AMT’s coronary and peripheral stents, VCBeat interviewed Dr. Liu Qing, founder of AMT.

Dr. Qing Liu pursued his academic studies and conducted postdoctoral research at Tsinghua University, Sichuan University, the University of Twente in the Netherlands, and Rice University in Houston, USA. He subsequently joined Celgene (Celgene Corporation) as R&D Director, overseeing the development of biomaterials and tissue engineering products. With over 25 years of experience in the research and development of biomaterials and medical devices, he specializes in the R&D and commercialization of medical devices.

While in the United States, Dr. Liu Qing was highly optimistic about 3D printing technology. He founded US-based 3D Biotek in 2007. Dr. Liu stated, “3D printing technology will see broader applications in the biomedical and pharmaceutical fields.”

3D Biotek has been researching the application of 3D printing technology and biodegradable materials for the preparation of fully degradable vascular stents since 2008, and once collaborated with internationally renowned companies, but later ceased cooperation due to commercial reasons.

In 2011, Dr. Liu Qing returned to China and founded Beijing Advanced Medical Technologies Co., Ltd., specializing in the research and development of 3D-printed vascular stents, including fully bioresorbable coronary and peripheral vascular stents. Subsequently, renowned experts in the international vascular stent field, Dr. Zhao Qinghong and Dr. Alex Nikanorov, joined AMT Medical Inc.

Dr. Zhao Qinghong and Dr. Alex both have many years of experience in the research and development of vascular stents and cardiovascular products at multinational corporations such as Medtronic and Abbott. Many of the products they helped develop are already being sold in international markets.

Through the efforts of the AMT team, they pioneered the world’s first 3D multi-axis curved-surface printing technology for polymer vascular stents.

3D multi-axis curved surface stent printing technology offers advantages such as rapid manufacturing, near-zero material waste, and energy efficiency and environmental friendliness, enabling the production of vascular stents with unique structures, high radial strength, and excellent flexibility and deliverability. Leveraging this innovative core technology, AMT Medical Inc. has been successively recognized as a Zhongguancun High-Tech Enterprise, a Zhongguancun "Golden Seed" Enterprise, and one of Beijing’s Top 20 Biopharmaceutical Enterprises (G20).

Furthermore, since its establishment, AMT Medical has successively received support from multiple programs, including the National Ministry of Science and Technology’s Key Project Support Plan under the 12th Five-Year Plan, the Major Special Projects under the 13th Five-Year Plan, the Zhongguancun High-Precision and Advanced Technology Project, the Strategic and Emerging Industry Incubation Project of the Beijing Municipal Science and Technology Commission, the Preclinical Research Project of the Beijing Municipal Science and Technology Commission, the Haidian Park Innovation Fund, and the Major Special Projects under the 13th Five-Year Plan of the Ministry of Science and Technology. The company has accumulated approximately RMB 30 million in government funding. AMT Medical’s fully bioresorbable coronary stent has been appraised by an expert panel organized by the Ministry of Industry and Information Technology as reaching a domestic leading level.

As a technology-driven enterprise, Liu Qing stated, “In terms of patent layout, we place great emphasis on international patent applications. The company has already obtained multiple domestic and foreign invention patents for related technologies. AMT Medical Inc. aims to become an internationalized company.”

The AMSorb™ stent is manufactured using 3D multi-axis curved surface printing technology, featuring a novel fully bioresorbable stent structure. Compared with laser-cut bioresorbable stents, the AMSorb™ stent incorporates AMT Medical’s proprietary spiral-arranged closed-loop unit structure, with smooth strut surfaces and circular strut cross-sections.

This stent structure represents the optimal design selected by AMT Medical after evaluating over eighty different configurations. It not only offers excellent flexibility and radial support but also allows the stent struts to conform closely to the vessel wall. Furthermore, compared with laser-cut stents featuring square cross-sections, the circular cross-sectional area of these stent struts is reduced by approximately 50%, thereby accelerating endothelialization and shortening the time required for complete degradation and absorption in vivo.

Based on animal experimental data, the AMSorb™ stent maintained vessel patency with no thrombus formation, and its radiopaque markers at both ends were clearly visible. Optical Coherence Tomography (OCT) demonstrated good apposition of the implanted stent to the vessel wall, with complete endothelialization achieved within one month post-implantation. The stent had fully degraded three years after implantation, and blood flow at the implantation site remained fully patent.

The AMSorb™ stent is made of PLLA material. Liu Qing introduced, "This medical-grade material is imported from abroad, costing about 40,000 yuan per kilogram." So, are AMT Medical's stent products very expensive?

“We employ an additive manufacturing approach, specifically utilizing 3D multi-axis curved surface printing technology to fabricate vascular stents. A key feature of this technology is its material efficiency, resulting in negligible waste,” introduced Liu Qing. He noted that this technique enables one-step product formation, eliminating the need for carving or post-processing to address surface finish requirements.

Notably, this technology offers exceptional processing efficiency: it takes only one minute to print a finished coronary stent from raw materials, and the printed stents require no polishing or other surface cleaning treatments. Consequently, the manufacturing cost of the stents is highly competitive.

The peripheral stent developed by AMT Medical is primarily designed to treat lower extremity arterial occlusion, a common complication in patients with diabetes. The device utilizes modified PLLA material, which offers superior resistance to bending fatigue, and features a single-sided outer drug coating that facilitates vascular repair and endothelialization. Clinical trials for this product have currently been applied for both domestically and internationally. Liu Qing stated, “Due to differences in the number of trial cases, the peripheral stent may reach the market earlier than coronary stents.”

AMT’s 3D printing technology is not only capable of producing vascular stents, but also excels in fabricating 3D tubular scaffolds with complex microporous structures, such as non-vascular stents and tubular tissue engineering scaffolds.

Currently, AMT Medical Inc. has a production line with an annual capacity of 30,000 stents. Its fully bioresorbable coronary stent project has been included in Beijing’s Key Engineering Projects for 2019. In addition to coronary and peripheral stents, AMT is also developing non-vascular stents.

In terms of financing, AMT Medical has received investments from institutions such as Beijing Daqing Biology, Beijing Tianfeng, Kaifeng Venture Capital, Guozhong Venture Capital, and Zhonghai Green, with a cumulative investment amount reaching RMB 100 million. Currently, AMT Medical is preparing for a new round of financing to support clinical trials for coronary stents and peripheral stents.

“Following the withdrawal of Abbott’s Absorb product from the U.S. market, AMT Medical Inc. has assumed an international leading position in the research and development of next-generation fully bioresorbable vascular scaffolds. Capitalizing on the favorable policy environment characterized by strong national support for the innovation of medical devices, we are highly confident in expediting the market launch of our novel fully bioresorbable vascular scaffold to meet the needs of the vast number of cardiovascular patients in China,” Dr. Liu Qing stated confidently in conclusion.